Welding torch devices are commonly used to connect metals together in manufacturing and in construction activities. One particular type of welding device is a gas tungsten arc welding (GTAW) torch, commonly referred to as a tungsten inert gas (TIG) arc welding torch. The TIG torch uses a tungsten electrode and an ionized inert gas to form an electric arc to the desired work surface. As with arc welding devices generally, large amounts of electric current are required to operate a TIG welding device. For safety and efficiency reasons it is desirable to insulate the operator of a welding torch from the welding current and the high frequency electrical energy utilized in the welding device.
Present torch head assemblies for TIG welding devices typically have a back cap that connects to a torch head. The back cap contains an electrode and connects to the torch head. The rear portion of the electrode extends from the torch body into the hollow body of the back cap. In operation, an inert gas is fed into the torch head and guided through a nozzle around the front portion of the electrode to the work surface. High frequency signals are superimposed onto the power supply providing electric current to the electrode in order to ionize the gas and create an electrical arc from the electrode to the work surface. The connection between the torch head and the back cap is important in that a poor seal will allow gas and high frequency electrical energy to leak out. Present seals on TIG torches only use a single sealing surface between the torch head and back cap to address this problem. Therefore, it would be advantageous to have better seal to protect an operator from the gas and electrical energy.
The high amounts of current used in the TIG process leads to high amounts of heat being generated at the electrode and in the power cable supplying the electricity to the electrode. The electrical rating of the torch head and cable assembly depends upon the amount of electric current the cable can safely carry without overheating. A power cable that is more efficient in dissipating heat can carry more current. Many power cables used in welding are bulky and not very flexible. A power cable possessing greater heat dissipation efficiency and flexibility is desirable.
As a result of the need for large power cables, larger handles must be attached to the torch head assembly to accommodate the larger cables. The larger handles can be difficult for an operator to grip. Also, various types of currently available TIG torch handles attach to the torch head using circular, friction-fit mating surfaces. In operation, undesired rotation may occur between the torch head and the handle. TIG torch handles using threaded surfaces to connect to the torch head also suffer from unwanted rotation due to the thermal expansion and contractions caused by the heat generated in operating the welding device. It would be advantageous to have a smaller handle that is easier to grip and that will form a connection with the torch head that will not rotate.